Signal responsive apparatus



June 17, 1952 J. P. ECKERT, JR., ET AL 2,600,744

SIGNAL RESPONSIVE APPARATUS 4 Sheets-Sheet 1 Filed Oct. 21, 1950 INVENTORSI JOHN -W. MAUCHLYv JOHN PRESPER ECKERT JR.

ATTORiEY J. P. ECKERT, JR, ET AL 2,600,744

June 17, 1952 SIGNAL RESPONSIVE APPARATUS 4 Sheets-Sheet 4 Filed Oct. 21, 1950 I N VEN TORS 2 JOHN W. MAUGHLY JOHN PRESPER ECKERT JR.

Patented June 17, 1952 EJNITED STATES PATENT UFFIJCE SIGNAL RESPONSIVE APPARATUS Johnlre perl ckert Jr l w n and J hn W- V Mauchlm Ambler, Pa, assignors to .Eckert-i Mauclily. Computer Corporation, Philadelphia,

Pa., a corporation of Pennsylvania Application OctoberZl, 1950,. Serial No. 191,401

11 Claims. 1

This invention relates; 20. apparatusjointly re sponsive to impulse groups.- arriving over a plurality of channels and more particularly to an impulse responsive network of the type delivering at its output a signal reflecting properties present in all its input channels.

This invention provides an apparatus responsive to impulses or trains of impulses which arrive over a plurality of channels. The apparatus does not respond to each impulse individually, but to each group ofimpulses delivered concurrently by the several channels. The output impulse or impulses produced by the apparatus is determined by the energizing impulse group. In this way, the apparatusproduces a response which is a signal impulse or train of impulses uniquely reflecting the properties of the impulses. or trains of impulses arriving over the signalchannels.

Accordingly, it is a principal object of the invention to provide a new'and improved impulse responsive circuit;

Another object of the invention is to provide a new and improved circuit responsive to signal impulse groups made up of impulses concurrently arriving over a plurality of signal channels.

Yet another object of the invention is to provide a new. and improved circuit for producing unique output signals or impulse trains in response to energizing impulse groups.

Still another object of the invention is to pro vide an impulse responsive circuit delivering timed output impulses or trains of impulses.

A further object of the invention is to provide a new and improved like-unlike response circuit for comparing signal impulses or trains of impulses.

Yet a further object of the invention is to provide a new and improved circuit for inverting impulse-trains.

Another object of the invention is-to provide an impulse responsive circuit having high reliability and accuracy of response.

Yet another object of the invention is to provide an impulse responsive circuit permitting arbitrary suppression of its output signals.

The foregoing and other objects oi the invention will become more apparent as the following detailed description of the invention is read in conjunction with the drawings in which:

Figure 1 illustrates schematically a two-stage impulse responsive circuit embodying the invention,

Figure 2 is a timing diagram illustrating the Referring to Figure 1, numeral ll designates an impulse receiving terminal. Terminal it; may receive impulse trains having a.predetermined repetition rate which arehcharacterizedhby the presence or absence of a.positive goingimpulse in given impulse positions. Likewise,v an impulsereceiving terminal l2 may receive animpulsetrain of. the same repetition. ratelalso characterized by the absence. or presence. of, a positive-going impulse. in given impulse. .posi.-. tions. Although different impulse trains maybe received by. the terminals Iland IZ, respectively, corresponding impulses should appearsimultar eous y and h v ua dura ions.

Imp l e ivins. terminal ll isreturned to roundpote ti hrou h fia ac ie an l nked to the n e ontr le tre e. Q. of a buffin v lv 5 hro h. andu tor. I .The electrode, FM is gativ iased by i sre urn to negative bus 2! by a grid,resi stor ll. The or l cnc nductin bu fe valve. 5. o o io v etmmer i llv, apwm 6LT- Th mps va h s WX i YfiQIlPlQ lestr de e urn d. t sr unclvth i s a 1?- st r I 9, it ca hode Ree $5.50 ele trode, 23 directly l nked to grou d pote tial, hil in reen. l tr de. i llrl ss. a p itiv b s wan .re rne t rmra. ilirpush aby a a ac t r 5..- he eodesic? he biif 'i is v h I5 is returned. to positive bus fillthrough an anode resistor 27.

The circuit which. connects to impulse receivin e minalll ss milar e i u t onnecting to impulse'receiving terminal H. A. bypass pac r. 3 is d ed. etwe n e te minal I2 ndsmnn Whi e n 9 5 6 nlss 12. with the innercontrol electrode 3Q o fa buliing valve 35. The bufling valve 35 which is normally nonconducting has its inner control electrode 34 returned to negative bus 2I through a grid resistor 31. The auxiliary control electrode 38 of bufling valve 35 is returned to ground potential through the resistor I9; the cathode 42 and suppressor electrode 43 are directly linked to ground potential; and the screen electrode 44 is joined to positive bus Ill and returned to ground potential through a bypass capacitor 45. The anode 46 of bufling valve 35 is joined to the anode 26 of buifing valve I5.

A conventional type gating valve 56 which is normally nonconducting has its inner control electrode joined to the impulse receiving terminal I I, its auxiliary control electrode 52 linked to the impulse receiving terminal I2, and its cathode. 53 and suppressor electrode 54 returned to ground potential. The screen electrode 55 of gating valve 56 is connected to positive bus 18 and returned to ground through a bypass capacitor 56 while the anode 51 is returned to positive bus 90 through the anode resistor 53 and further joined by means of a coupling capacitor 58 to the auxiliary control electrodes I8 and 38, respectively, of the bufiing valves I5 and 35.

A positive impulse passing from impulse receiving terminal I I to the inner control electrode I4 of the bufflng valve I5 is delayed by the network comprising capacitor I3 and inductor I6. When received the current surge resulting through the anode circuit of buffer valve I5 develops a negative-going signal on its anode 26. This signal is delivered to the output line 28. With the removal of a positive signal impulse from the inner control electrode I4, the buffing valve I5 resumes its normal nonconductive state.

In a like manner, a positive impulse arriving from the impulse receiving terminal I2 is delivered to the inner control electrode 34 of the bufling valve 35 after a delay imposed by the network comprising capacitor 33 and inductor 36. The resulting conduction of the bufilng valve 35 gives rise to a negative-going voltage upon the anode 46. This voltage signal is delivered to the output line 28. With the removal of the positive signal from the control electrode 34, the buffing valve 35 resumes its normal nonconductive state.

A positive-going signal upon the impulse receiving terminal II is also immediately delivered to the inner control electrode 5I of the normally nonconducting gate valve 50; while a positive impulse upon the impulse-receiving terminal I2 is immediately delivered to the auxiliary control electrode 52 of this valve. The gating valve 50 remains nonconductive except when positivegoing impulses are concurrently delivered from terminals II and I2. In this case, the gating valve '58 becomes conductive. The current surge resulting through the anode resistor 59 produces a negative voltage excursion upon the anode 51. This negative-going impulse is passed through the coupling capacitor 58 to the auxiliary control electrodes I8 and 38 respectively, of bufling valves I5 and 35. The valves I5 and 35 are prevented from becoming conductive by the negative signal upon their auxiliary control electrodes I8 and 38 even though positive signals appear upon their inner control electrodes I4 and 34 respectively. It is noted that the negative signal delivered to the auxiliary control electrodes I8 and 38 of bufling valves I5 and 35 arrives before positive signals are delivered to the inner control electrodes I4 and 34. This assures nonconductivity of the bufling valves I5 and 35. To further insure nonconductivity of the valves I5 and 35, the anode resistor 59 may have a high resistance which in combination with the series capacitance of the gating valve 56 forms a network having a relatively long time constant. Thus, when the positive signals are removed from the control electrodes 5I and 52 of the gating valve 50, the current flow through the anode resistor 59 decays slowly to prolong the duration of the negative signal upon the auxiliary control electrodes I8 and 38 of bufling valves I5 and 35.

The output line 28 connects through a couplin capacitor 62 with the control electrode 63 of a normally conducting signal input valve 64; the control electrode 63 is returned to ground potential by means of a grid resistor 65. The signal input valve 64 has its cathode 66 joined to ground and its anode 61 returned to positive bus 99 through an anode resistor 68.

A signal timing valve 69 is normally conducting. It has its cathode 'II linked to ground while its anode I2 is connected to a signal output line I3 through a coupling capacitor 6i and joined to anode 61 of signal input valve 64. The control electrode I4 of the signal timing valve 69 is returned to ground through a grid resistor and is also joined to the signal output terminal of a clock pulse generator I6 through series connected inductor II and resistor 78. A capacitor I9 connects to ground from the junction of inductor I7 and resistor I8.

Signals appearing upon the signal output line 28 are delivered to the control electrode 63 of the signal input valve 64. Delivery of a negative impulse to the control electrode 63 renders the valve 64 nonconductive. However, the potential upon the anode 61 of valve 64 is not affected by its nonconductivity, as long as the signal timing valve 69 remains conductive. This is because current continues to flow through anode resistor 68 which is common to valves 64 and 69. When valve 69 is also rendered nonconductive by the delivery of a negative-going impulse to its control electrode 74, a positivegoing impulse is delivered to the signal output line I3. This is because the current flow through anode resistor 68 is diminished and the voltage drop across it lowered by the concurrent nonconductivity of valves 64 and 69. When the signal timing valve 69 is nonconductive, the conductivity of the signal input valve 64 acts to prevent the delivery of positive-going signals to the signal output line 13.

The clock pulse generator I6 generates negative pulses at a repetition rate which is equal to the repetition rate of the signal arriving at impulse receiving terminals I I and I2. The combination of capacitor 19 and inductor 'II acts to delay the arrival of a negative impulse from the clock pulse generator 16 to the control electrode I4 of the signal timing valve 69. The delay imposed is sufiicient to allow a negative impulse to arrive first upon the control electrode 63 of the signal input valve 64 (if such signal is delivered from signal output line 28). Under such circumstances, the signal input valve 64 is extinguished first, and the signal timing valve 69 is made nonconductive thereafter with the arrival of the negative clock pulse. In this manner, the clock pulses time the delivery of positive signals to line 13 which results upon the goncurrent nonconductivity of valves 64 and 6 Signals upon' the l anode 51 0f: the gating valve 59' are also--delivered-to the auxiliary: control? electrode SI of a signal input-"valve '82- throughthecoupling capacitor "Valve 3 8'2E*- has .its

signal output=line Sit-through coupling ica-pacie tor ill A signal'inputvalve 8.2: is normally. conducting and isassocia-I'Jed with a normally.- conducting signal timing valve 95.

"The: signal timing walvesst has its: cathodetfi joined-to ground: and :its anode 531 linked:- to'thc anode '-81' of 'thez signal input valve control electrode 53 oi the signal"v timing:=valve fifi isalso connected to thesignal outputterminal cl? the clbcltpulsegenerator 1&1 throughiian inductor ilfi connected: in series With-the: resistor 18. The-control electrode $3 of: valve .95; is also returned to ground? through a. grid. resistor: I I I A capacitor- IBZ' is connected in: parallel with the capacitor '1 9'.

The operation of 'valvestflz and .195. issimilar to theuoperationuoi valves 64 and. 63*. just; described. .AnegatiVe-signal delivered: to the auxiliary control. electrodej S-I- .ofrrthe: signal: input. valve 82 from; the 1 anode 'tfla of: gating. valvemakeslvalve aiiztnonconductiveh A negative: signal receivedrthereaiter by the control electrode 98 of the signal timing valve 95 makesvalve- 95' nonconductive. fWitnboth valves 82 and 95 nonconductive aspositiveegoingrimpulse is de livered: toi-the1signalioutput line 89.-

.I'he.signalsoutputglineifie is-iconnected-v to the input of a; .delaylzline" i535. having 1 an input; re-

sistor 'I 3.3. connected :to ground. The delay; line;

I05 may comprise two series inductors Illconnected;betweenithe line 63* and acline I39; ca-

pacitors I%'I lkxconnecting' from "the ends of the inductors:.:i8.1 atoground; potential; The. delay linteIIilEz-imposes adelay; on signals passing from line-8.9 to line. IJe wliichis approximately one pulserperiod at. the: clock pulse repetition rate.

. The: portion of. the impulse responsive circuit described. thusfar may be considered one stage of avtwoi-stage-znetwork. The second stage is in r ing.:bufiing:.valve. I35. Line IE9; is:a'1so; directly. connected. to the auxiliary.- control' electrodexltl ofthe. gatingrvalve l501i The anodes I26 andd46- respectively ofzbuffingvalves H5 1 and I 3.5 are I returnedto theplus efl bus: throughan anode. resistor: I 2 1: and connect to a signal output :line I 23. The: anode I 51 of the gating valve I 50 returns to the positive bus Bil-through ananoderesistoi I58 and connects-bymeans -of acoupling capacitor- I58 to the auxiliarycontrol-electrodesIla-and I38, respectively,- of the bufiing valves II5= and I35; anode --I 51 alsoconnects- -to the inner control electrode 80-of the signal input valve -82iin.series1 withr aresistor I18;

A positive impulse: upon .the signalioutputline 13 makesrthebufiingnvalvei I I -5..:conductive* after a given delay. to.pro.duce'. a negative signal upon the outputzline I12 8.; Likewise; an positive-going impulseupon the. signalioutput line' m9; renders signal buffing valvesIzconductive after a; given period, alsoproducing. a negative-going. signal upon thezoutputline 128: 'Whenpositi-ve-going impulses are. concurrentlyv present t upon" the; signalzoutputdines. 1.31" and I09; the; gating valve I 5% becomes: 'conductive;.: and: produces: a negativegoing signalupon its anode I51. This signal is delivered toxthe auxiliary'controli electrodes I is and I38, respectively;of'valves II5and 635i. and prevents; thein conductivity. Thenegative-going impulse onzthelanode: I51 ofrthegating valve IE9 is. also :delivered: to theinner control electrode til of; the; signal input .valve'82- making this valve nonconductive. Thus, a; negative-going signal upon-the; inner control electrode 33 makes the signal: input .valve; 82;: nonconductive as does a negative signal uponrthe auxiliary control electrode 8| 'As:before;;therappearance of anegative clock pulse. on.-..the; electrode 98 ofthe signal timing .valvez9fieproducesa positive-going signal uponx-the line: 89.

The signal output line; I2 85 is:connected through a cQuplingLca-paciton I 62 to the. control; electrode I63 of a signal input valve I64; the control electrode- I63; is .returnedto ground through a grid resistor .-I-65.. Thesignal input valve Ifi l'which is normallyconductiverhas .its cathode I 65 returned to ground. and. its. anode Nil-joined topositive bus 9fl through ancanoderesistor I68; .Tlieanode I61.of.valve:.I6Ilisczfurther'connected. to a signal outputdine I13.

Anormally conductingrsignal timing valve Its, associated .with the. signalinputvalve I 6 3, has its anode. I12 linked. to.:anode 1610f valve IE4 and its. cathode I1I grounded. The controlelectrode I14';of thesignal timing-valve I69.ais returned to ground through agridiresistor I15'and connected with the signal output terminal of the clock pulse generator 161 through .an inductor I 11' connected The junction of conductor I11. and. resistor I18.-is' returned to ground through. a. capacitor I19. Thecontrol electrode :I.14'of. valve I69; is .also joined to' the cathode -.of a crystal .diode .IBI. The anode of crystaldiodellal isl'returnedto a negative bus 8 through a leading resistor I821. linked tov asuppressing signal terminal I53.

-Negative'signalsrfrom the line I28 are delivered totthe control-electrode1l63 of. the normally conducting signal inputvalve I64 to make this valve cumstanceseven-though a negative going inipulse'deliveredtothecontrol electrode H53 of the signal input valve i IBA- causes" nonconductivity, the-signal output line I13"will not be driven-positive.

' 'The signal output-line I13 is alsojoinedto the control electrode I86 of inverter valve I81 through a coupling capacitor I88; the control electrode I86 is negatively biased by its return to the negative bus 2| through a grid resistor I89. The signal inverting valve I81 is normally nonconducting; it has its cathode I99 grounded and its anode I9I returned to positive bus 90 through an anode resistor I92. The anode I9I is also linked to a signal output line I93.

Positive-going impulses from signal output line I13 are delivered to the signal inverter valve I81 producing a current surge in its anode circuit. This develops a negative signal impulse which is delivered to the signal output line I93.

Consideration is now had of the overall operation of the impulse responsive circuit shown in Figure 1. Upon the arrival of a positive impulse on the impulse-receiving terminal II, when no impulse is received by the impulse-receiving terminal I2, bufling valve I is made conductive producing a negative-going signal upon the output line 28. This negative signal from the output line 28 is delivered to the control electrode 63 of the input valve 64 making it nonconductive. The arrival of a negative clock pulse upon the control electrode 14 of the signal timing valve 66 makes it nonconductive also developing a timed positive-going signal upon the signal output line 13.

In the absence of a signal on the output line I09, delivery of a negative impulse to the inner control electrode II4 of the bufiing valve II5 from the signal output line 13 produces a negative-going signal upon the line I28. This negative signal is delivered to the control electrode I63 of signal input valve I64 making it nonconductive. A positive-going impulse is delivered to the output line I13 when the signal timing valve I69 becomes nonconductive in response to a negative clock pulse upon its control electrode I14. The signal inverting valve I81 produces a negative output signal from the positive signal developed on the output line I13.

In the absence of a positive impulse upon the terminal I I, the arrival of a positive impulse upon the impulse-receiving terminal I2, in a similar manner, results in the conduction of the bufling valve 35 to produce a negative-going signal upon the output line 28 which is received by valve 64. As before, with the input valve 64 made non-conducting, the cutoff of timing valve 69 develops a positive signal which is delivered to the signal bufiing valve II5. Valve II5 becomes conductive delivering a negative signal to the input valve I64. Valve I64 is now out off to develop a positive output signal on the line I13 when signal timing valve I69 is cut off.

If a positive impulse is delivered to the impulse receiving terminal I I at the same time a positive impulse is delivered to the impulse receiving terminal I2, the gating valve 50 is made conducting to prevent the delivery of a signal to the output line 28. However, a negative impulse is delivered to the auxiliary control electrode 8I of th signal input valve 82, driving it to cut off. A positive timed impulse is developed upon the line 89 under the cutoff of the signal timing line 95 with its receipt of a negative clock pulse. The delay line I05 receiving the positive impulse over line 89 delivers this signal to the output line I09 after a delay of about one pulse period. In other words, the delay imposed by the line I05 is such that a signal is delivered to the line I89 at the time when the next following clock pulse arrives upon the control electrode 14, 98 of signal timing valve 69, 95. This assures the simultaneous arrival of signals appearing concurrently upon the signal output lines 13 and I09.

The case has already been considered in which a signal output appears upon the line 13 in the absence of a signal upon the line I09. When a signal arrives upon the line I09 in the absence of a signal upon the output line 13, the buffing valve I35 is made conductive developing a negativegoing signal upon the line I28. The negative signal from line I28 cuts off the signal input valve I64, so that when the signal timing valve I09 is made nonconductive by the receipt of a negative clocking pulse, a positive-going impulse is produced upon the output line I13.

In a case where positive output signals are delivered over both lines 13 and I09 at the same time, the gating valve I50 is caused to conduct preventing the development of a negative-going signal upon the line I28 and delivering a negative impulse to the inner control electrode of the signal input valve 82. The signal input valve 82 is thereby made nonconducting. The arrival of a clock pulse cuts ofi the timing valve 95. This develops a positive-going impulse on line 89 which is passed through the delay line I to arrive upon the line I09 one pulse period later. If a signal also arrives upon the line 13, with the arrival of the impulse upon the line I09, th cycle of events just described is repeated. That is, a negative signal is delivered to the signal input valve 82 and a timed positive signal is passed through the delay line I05 from the line 89 to the line I09.

When the cycle of events just described is to be repeated many times, a great advantage derived from the use of signal timing valve 95 is that a slight timing error is not increased with each cycle. This is so because the signal arriving at the signal input valve 92 is retimed for each of said cycles.

It should be noted that negative impulses upon both the inner control electrode 80 and the auxiliary control electrode ill of the signal input valve 82 cannot appear at the same time. This will become clear by considering that it is necessary that concurrent positive impulses appear upon both the impulse-receiving terminals I I and I2 for the delivery of a negative impulse to the 4 auxiliary control electrode 8| of the signal input valve 82. In this event, a negative signal is not developed upon the output line 28 resulting in the absence of a positive signal upon the line 13. However, if a negative impulse is to be delivered to the inner control electrode 80 of the signal input valve 82, a positive signal upon the line 13 is required as well as a concurrent signal upon the output line I09. Thus, when a negative signal is delivered to the auxiliary control electrode 8 I, the delivery of a negative impulse to the inner control electrode 80 of valve 82 is not possible.

Referring now to Figure 2, together with the circuit shown in Figure l, a clock pulse is generated upon the initiation of each pulse position. A positive impulse arriving at terminal II, at impulse position 1, is delivered to the input of buffing valve I5 after a given delay. Because a positive impulse does not appear upon the terminal I2, during impulse position 1, a positive signal is delivered to the output line 13. This signal is timed by the arrival of a delayed clock pulse at the input of the timing valve 69.

After being delayed, the signal upon line 13 arrives upon the input of the bufiing valve II5. With the absence of an input signal to the bufiing valve .1 I 35. betweenpulse. positions, .1. and 2, a positive signal. is delivered ,over. the iout'put line I13, being-Jtimed-by. .the {arrival of. a properly :delayed input. clooksignalrat the ,timing .Valve .169.

The arrival of impulses on both terminals;II

gating valve -I iifl -ppon, bothits input electrodes produces an output signal pr n the "delivery of an impulse to the HD6113: while .delivering a signal. to line 89.

A positive impulse .arrives upon terminal I2 at; impulse position 4, effectingdeliveryyof a positive. signal upon line-J3. An, output'signal-is developed by the gating valve -I 50 7 during 1 ;-pulse position 4. a This results-from the delivery at this time f-signa1s uponboth. inputi-electrodest-oi valve I50. the. signal online 13 while, the-.other electrode receives, the signal appearing .prev-iously (during pulseposition 3-) upon line 89.- Thisoutput signal of gating valve I5I);.prevents;a signal output upon dine I13 ,duringimpulse position 4, and

effects delivery of .an. impulse=signal to line-83.

At impulse position 5, :the arrival-=,of;-a positive impulse .upon thie terminal I I also delivers a-positive impulse to. theplines 13. ,An output signal is again delivered in pulse. position 5 by gating valve I50 becauseof the receipt of signals-uponboth itsinput electrodes This/results in nosignal pulse being received by the: output line 1-13 in pulserposition ,5 while thesignalis delivered to line 89.

An impulse .doesnot arriveupon eithergterminal H or.I3 .duringpulseiposition ,6.. However, in pulse position 6,..a signal is ,delivered ,to .the input of bufling valve, I35. This signal is derived, after being suitably delayed .by .delayline 105, from the signal appearing ,upon line .89 during pulse position 5. The .output signal. frombufling valve I is timed .by valve I'59.Whioh produces in pulse .position- 6, ,an output signal. upon .line I13.)

In pulse position '7, the .absence .of impulses uponv the terminals ,I I. and I2 isaccompanied by the absence of an, output. impulse upongthe line I'I3.,

The presence of. impulses :upon both terminals II and I2 inlpulsepositiont results-in thedelivery of a positive. impulseuto the vline.189.,. No signal impulse isdeliveredto. they line 1 .I I3 in this pulse positions Thepresenceof signal impulses upon the terminals. I I and I ZE-In pulsepositi-on .9 likewisep'roduces a signal upon .line 89.; However, an impulse is delivered .upon the .line I13. This isbecause an inputsignal is receivedby the gating valve .135 .derivedirom line .89. after a pulse .period delalh.

In pulse position 10,,the arrival. of .a signal upon terminal I2 results in delivery of a signal to .the line 13., In this case amoutputsignal is delivered by. he at ng .valve. I511 becauseof the receipt of, signals .ifrom-.,11ne J3, as wen as One electrode of .valve 150 receives 10 'from line, 89. The output signal ,irom gating valve I prevents :tlle deliveryofa signal to the line I13 and effectsgthedeliverygof a signal to line 89.

The;presence ofan impulse uponterminal II in pulse ipositionil results vin a signal :being delivered to line .313. An output signalis deiiveredv by. gating ivalve I50 because as in the previous, case, input signals are ,derived from line 89gand I3.

In pulse position 12, nosignalsarereceived by the terminals I- I and I 2. However, an input signal is'deliveredto; the buifingpvalvel 35 from line 89; after being, subject-to a :cne-pulse position delay. Theou-tput signal fromthebuffing valve I 35 in thepresenceof a clockpulse input. to the timing valve I5 fliproducesan impulse.- signal upon thejine I73. -TIowever, in this instance, the clock input signal tothetimingvalve I631is suppressed, thus-preventing delivery of,,,an,.impulse signal to line ,I'I3.,: As previously-noted, the presence of a positivesignal upon .thelterminal I83,.(Figure 1) actsto suppressthe delivery-of-clook signals tothesigna1 timing -.valve. 169.

Pulse positions ;1,3;an d 14 clearly illustrate that the .arrivaloi. positive impulse upon both rterminals II and 12in Fpulse positionlS withfthe absenceof impulses :arriving. at, pulse position. 14 results in the :delivery, of ;an impulse :to line I73 in pulse position, 14.:

From; the. .abovedes'cription it may be observed that the :output signals ydelivered upon the .line I 'i' 3, are. determined by the :sequence or series of impulses delivered ;.upon-. the .terminals I. I and. I 2.

With given combinations zofgimpulses. upon terminals II and ,-I2,;-cor,responding responses are obtained comprising .;unique .impulseeombinationsin timeordered patterns. The :impulse responsive apparatus here described .may be adapted for various uses-by those skilled in the art.

It may also; beinotedthat, the circuitshown in Figure 1 may be .used to addr'binary. numbers. For example, each impulse. arriving upon the terminals "I I and,.I 2 may be considered .to repre sent ithenumeralsql .(one), whilethe absence not an impulse ,ina pulse position can, be .used to represent the ;numeral. 0 (zero). For this example, consider; pulsepositions .1 through ;'7 (Figure 2);. The least: significant figure. appears in pulse position 1. Thl1S .the :signal impulse train arriving, uponterminal .I I represents the binary number 00100111 ,Thesignalinputtrain correspondingly arriving at terminal I21 represents -:the binary number 0001110. The output response train arriving. upon. line I73; for the .said Jfirst seven pulse.positions, ,the least significant figure being representedin pulse'position 1, corresponds to the 'binary number 0100001; Thus, it is evident that signal trains upon terminals II and -I2 representing.-binary numbers cause the apparatus .toupro'duce .an output signal train representing theiri binary sum.

uponfeithe-r. of theterminals II or. Iz butynot both, then a signal impulse is delivered over the line 13. If positive impulses are received by terminals II and I2 at the same time, then an output signal is delivered over the line 89.

This circuit also provides a statically responsive network when one output lead is directly connected to the anodes of bufiing valves I5 and 35, and the other output lead is directly connected to the anode of gating valve 50. In this case, the duration of output signals corresponds to the duration of input signals.

The circuit now under consideration may be utilized for comparing input impulses. For example, like-unlike comparison of signal trains concurrently arriving upon terminals II and I2 respectively provides the following results. If comparison of these arriving is identical, no output is delivered on the line I3 while signals are delivered to line 89. When the signals are presented to either line II or I2 and none arrives upon the other, the circuit produces an unlike response by delivering a signal to the line I3, while no signal is delivered to line 89. This comparison circuit may be utilized to sound an alarm or shut down equipment when an unlike response by the circuit indicates malfunctioning of equipment delivering signals to this circuit.

Another mode of operation and utilization of the first stage portion of the circuit shown in Figure 1 is to invert signal impulses presented to one of the input terminals I I, I2. For example, if signal impulses delivered to terminal II are to be inverted and delivered over output line I3, an impulse signal train characterized by a repetition rate substantially identical with that of the signal delivered to terminal II and having an impulse present in each impulse position is delivered to terminal I2. It is thus apparent that when an impulse is delivered upon terminal II an impulse will be received by terminal I2, and no signal will be delivered to the output line 13. However, when an impulse is not delivered to terminal II in a predetermined impulse position, the impulse which is present upon terminal I2, results in an output signal upon the line I3. Thus, for each impulse arriving upon terminal II no impulse is delivered to line l3, while with the absence of an impulse in a given pulse position upon terminal I I, an impulse is delivered over the output line I3. This effectively results in inverting a signal train arriving on the terminal II, that is, presenting an impulse where one was originally absent and removing an impulse where one was originally present.

This inverting process is especially useful in means employed for binary computation. When a signal is so inverted and used in binary computation it is usually designated as the ones complement.

Referring now to Figure 3 which shows a modified impulse responsive circuit, an impulse receiving terminal 20I is connected to the control electrode 202 of a bufilng valve 203. The control electrode 202 of the valve 203 is negatively biased by returning through a grid resistor 204 to a negative bus 2|. The buffing valve 203 which is normally nonconductive has its cathode 2E5 returned to ground potential and its anode 200 joined to a positive bus 92 through an anode resistor 206.

An impulse receiving terminal 2 is joined to the control electrode 2I2 of a bufiing valve 2I3. The control electrode 2I2 of bufiing valve 2I3 is negatively biased by its return to the negative 12 bus 2| through a grid resistor 2I4. The bufi'ing valve 2I3 which is normally non-conducting has its cathode 2I5 returned. to ground potential and its anode 2 I 6 linked to the anode 206 of the bufiin valve 203.

The impulse receiving terminal 20I is also joined to the inner control electrode 2I9 of a signal gating valve 220, auxiliary controlled electrode 22I of this valve. The signal bufling valve 220 which is normally non-conductive has its suppressor electrode 222 and cathode 223 linked to ground potential, its screen electrode 224 joined to a positive bus 10 and by-passed to ground through a capacitor 225, and its anode 226 returned to the positive bus through an anode resistor 221.

The anodes 200 and 2I6, respectively of bufling valves 203 and 2I3, connect with the control electrode 229 of a signal input valve 230 through a series connected coupling capacitor 23I and an inductor 232. The control electrode end of inductor 232 is connected to ground through a grid resistor 233, while its other end is joined to ground by an input capacitor 234. The signal input valve 230 which is normally conducting has its cathode 235 grounded and its anode 236 joined to positive bus 90 by means of an anode resistor 231. The anode 236 of valve 230 is also linked to the anode 226 of the gating valve 220 by means of a coupling capacitor 238.

A signal timing valve 240 associated with the signal input valve 230 has its control electrode 24I connected with a clock pulse terminal 242 through an inductor 243. The control electrode end of inductor 243 is returned to ground through a grid resistor 244 while its other end is passed to ground through an input capacitor 245. The signal timing valve 240 which is normally conducting has its cathode 246 linked to ground and its anode 24! joined to the anode 236 of the signal input valve 230. AnOde 241 of valve 240 is further coupled to a signal line 250 by means of a coupling capacitor 249.

The impulse receiving terminal 20I may receive impulse trains having a given repetition rate and which are characterized by the presence or absence of a positive-going impulse in given impulse positions. Likewise, terminal 2II may receive an impulse train of the same repetition rates also characterized by the absence or presence of a positive-going impulse in given impulse positions. The presence of a positive impulse upon terminal 20I makes bufiing valve 203 conductive to produce a negative-going signal in its anode circuit. This negative-going signal is delivered to the control electrode 229 of the signal input valve 230 to make it nonconductive. In a similar manner, a positive-going signal upon the terminal 2II renders bufiing valve 2| 3 conductive to develop a negative-going signal in this anode circuit. This negative signal likewise drives the signal input valve 230 to cutoff. When the signal receiving valve 230 is nonconductive due to the presence of a positive-going impulse upon one of the terminals 20I or 2I I, cutoff of signal timing valve 240 causes delivery of a positive-going signal to the output line 250. The signal timing valve 240 is cut off by each negative clock pulse that arrives from terminal 242. The clock pulse repetition rates is the same as the repetition rate of the signal trains delivered to terminals 20I and 2| I.

When positive impulses are received by terminal 20I and 2 at the same time, the positive swing of electrodes 2 I 9 and 22I renders the signal 1 timing valve 236.

gating valve 226 conductive. Uponzconduction, a negative signal is developed upon .theanode 226 of valve 226. This negative signal is delivered to the anodes 236 and 2411, respectively, of valves 236 and 246, toprevent their positive excursion, thereby inhibiting the delivery of a positive-going signal'to the 1ine250. Thissuppression of an output signal on line .250is assured by the inductor 232 and capacitor 234 which delay the delivery of the negative-going. impulse from the bufiing valves 203 and .2 I 3 to the control electrode 223 of the signal input valve 236. This allows the prior arrival of the suppressing signal. Furthermore, the suppressing signal delivered by the gating valve 226 may be prolonged. so that it remains present until after the negative signal has been removed from the control electrode229 of input valve 236. This prolonged signal may easily be obtained as follows: Make the resistance of the anode resistor 221 sufiiciently high so that its combination in series with thecapacitance of the gating valve 223 forms a network having a relatively long time constant.

The clock pulses on terminal 242 are delayed by the combination of inductor 243 and-capacitor 265 before reaching the input electrode'i24l of The clock pulse is delivered to the input of valve 246 after the-inputsignal is received by valve 230 in order to time the signal output to line 250.

The anode 226 of the signal gating'valve 226 is also coupled to the auxiliary control electrode 353 of a signal input valve 254 by means of a coupling capacitor 255. The electrode 253 -is also returned to ground through a grid resistor 252. The input valve 254 which is normally conducting has its suppressor electrode 256 and cathode 25'! directly linked to ground, its screen electrode 258 joined to positive bus 10 andreturned to ground through by-pass-capacitor 259,

and its anode 266 returned to positive bus 36 by means of an anode resistor 26 l.

A normally conducting signal timin valve 262 is associated with the signal input valve 254. The control electrode 263 of the signal input valve 262 receives negative clock pulses from'the terminal 242 through a delay network comprising an inductor 264 and an input-capacitor 265. The said control electrode 263 also is' returned to ground by means of a grid resistor 266. The cathode 261 of valve 262 is grounded while the anode 268 is linked to anode 266 of valve 254 and joined to a signal line 263 through a coupling capacitor 216.

A negative-going impulse developed in the anode circuit of gating valve 220 is also delivered to the auxiliary control electrode 253' ofsignal input valve 254 to make it nonconductive. Shortly thereafter, the signal timing valve-262 receives a negative clock pulse cuttingi-t off. This results in the delivery of a positive-going signal to the line 269.

The signal line 263 is connected to thei-nput of thedelay line 21!. Delay line 21-! comprises'series inductors 212, an input resistor 213 bridging the input end to ground, an output resistor-215 bridging the output end to ground, and'delaycapacitors each connecting an inductor end to ground. The output of delay line 21! connects to the signal line 216 through a coupling capaciter 2".

The delay line -21l passes signalsappearing on line253 to line 21-6 and-imposes a delay-of approximately one pulseperiodat said-given repetition rates.

nal 242 through a delay network 1343.

Thus, -if a positive: impulse: arrives: atith'etterminal :26 I, a positive. impulsezwill bedeliveredto the line 250. Ira positive. impulserarrivesxupon the terminal 2! I, ..a .positive impulsesalso is :delivered to the line 250. If; however, .;positive*im pulses .appear on the terminals-2M and 211 at the same time, an impulsewillnotbe delivered tothe line 250.. However, .a positive impulse will be delivered to the line .216, one pulse period later.

iary control electrode 32I of the signal gating valve 326. The anodesof bufiing valvest303'and 3I3 are returned 'to thepositive bus'90 through an anode resistor-331 andarelinkedto the control electrode of a. signal input valve "336* through a delay network 332.

The signal gating valve 326 has'iitsianode 326 returned to positive bus :through :an anode resistor 321 and linked with the anode of .the signal input valve 330 through 'a couplingwcapacitor 338. Anode 326.of the signal 'gatingavalve 326 is also linked to theinner control electrode 353 of the signal input valve254 bymeanszof a coupling capacitor 355. The control electrode 353 is returned to ground througha gridrreslstor A signal timing valve 340 associated .Withtthe signal input valve 330 receivestnegative iclock pulses upon its control electrode from the :termi- The anodes of valves 330 and 340 are returned .to a positive bus 36 through an anode resistor1331 and are joined to a signal output line 350.

The operation of valves 303, 3l3, 326,'.336 and 336 are respectively similar to the operation of valves 263, 213, 220, 230, and 240, previously. described. Thus, when a positive-goinguimpulse arrives upon the line 256 a positive impulse is delivered to the line 356. When a positive'impulse arrives upon theline 216, a positive-going impulse is also delivered to the line 350. When positive impulses arrive upon the lines256 and 216 at the same time, a positive impulse is not delivered to the line 350,hoWever, a positive impulse is delivered to the inner control electrode 3530f .the signal input valve 254. TlllS'I'ESlllbSiill a positive impulse upon line 216 after a delayof approximately one impulse period. Negative impulses cannot be received atthe same time by both control electrodes 353 and 253 of thesignal input valve 254 for reasons-already explainedin connection with Figure l.

A signal inverting valve 366 has its "control electrode 36I joined to the signal output line-356 by means of a resistor- 362. The said control electrode 36l is negatively biased by returning to the negative bus 36l through a grid resistor 363. The cathode 364 of the signal inverting valve 366 -is grounded, and the anode 364 is returned tive impulse upon the output 'linev361.

If like sets of impulse trains are delivered to the respective impulse receiving terminals of the impulse responsive circuits shown in Figures 1 and 3, these circuits will deliver output signals having similar time ordered impulse patterns.

The first stage portion of the impulse responsive circuit shown in Figure 3 may be employed as previously described for the utilization of the first stage portion of the circuit shown in Figure 1. In this case, the circuit may comprise bufl'ing valve 203, buffing valve 2|3, gating valve 220, signal input valve 230, signal timing valve 240, signal input valve 254, and signal timing valve 262. This provides the circuit with two signal output lines, namely, lines 250 and 216. The output response of this circuit to input signals is similar to that of the corresponding portion of the responsive circuit shown in Figure l.

The impulse responsive circuit shown in Figure 4 is adapted to receive trains of negativegoing impulses upon its impulse receiving terminals 40| and 402. This impulse trains which arrive upon terminals 40| and 402 have the same repetition rate and are characterized by the presence or absence of a negative impulse in given pulse positions.

Terminal 40! is connected to ground through a grid resistor 403 and joined to the inner control electrode 404 of signal buifing valve 405. The impulse receiving terminal 402 is also returned to ground through a grid resistor 405 and joined to the auxiliary electrode 401 of the buflEing valve 405. The signal buffing valve 405 which is normally conducting has its suppressor electrode 4 linked to a positive bus 10 and returned to ground through a by-pass capacitor 4| I The anode 4|2 of valve 405 returns to a positive bus 00 through an anode resistor 4|3 and is also connected to the control electrode MB of a signal inverting valve 4|'| by means of a coupling capacitor 4|4 through a delay network 4 5. The delay network 4 5 comprises an inductor and an input capacitor 4|! bridged to ground from the input end of said inductor.

The inverting valve 4 1 which is normally nonconducting has its control electrode negatively biased by returning to a negative bus 9, and its cathode grounded. The anode of inverting valve 4| 1 connects to positive bus 90 through an anode resistor M9, and is also joined to a signal line 42| by means of a coupling capacitor 420.

The arrival of negative impulse upon either one of the impulse receiving terminals 40| and 402 renders the signal buffing valve 405 nonconductive to develop a positive voltage excursion upon the anode 4|2. This positive impulse is delivered to the control electrode of inverting valve 4|| which becomes conductive and delivers a negative-going impulse to the signal line 42 The signal input terminals 40I and 402 are also connected respectively to the control electrodes 420 and 42| of a pair of parallel connected gating valves 422 and 432. The gating valves 422 and 432 which are normally conducting have their cathodes 423, 433, grounded and their anodes 424, 434 returned to positive bus 90 through an anode resistor 435.

A normally nonconducting sign-a1 inverting valve 438 has its control electrode 439 joined to the anodes 424, 434 of the gating valves 422 and 432 by means of a coupling resistor 440. The control electrode 439 of valve 438 is negatively biased by returning to negative bus 30| through a grid resistor 44l.

The cathode of signal inverting valve 438 is grounded, while the anode 442 is linked to positive bus through an anode resistor 443 and joined to the control electrode 4| 1 of inverting valve 4 1 by means of a coupling capacitor 444.

If negative signal impulses do not arrive upon both of the terminals MM and 402 at the same time, at least one of the gating valves 422, 432 remains conductive. This prevents a positive voltage excursion of the anodes 424 and 434 of valves 422 and 432. However, when negative impulses arrive upon both of the terminals 40| and 402 at the same time, both gating valves 422 and 432 are concurrently cut off to produce a positivegoing voltage excursion upon their anodes 424, 434. 1

The delivery of a positive-going impulse to the control electrode 439 of inverting valve 438 produces a current surge in the anode circuit of this valve. The resulting negative voltage excursion upon anode 442 of the signal inverting valve 438 is delivered to the control electrode 4|6 of inverting valve 4|'|. This prevents the positive excursion of control electrode 4|6 due to delivery of a positive impulse from the output of the bufiing valve 405. The delay network 4| 5 assures the suppression of the positive impulse to valve 4|'| from bufiing valve 405 by delaying its delivery until after a negative impulse has arrived at valve 4|'| from inverting valve 438. Furthermore, the duration of the negative suppressing impulse from valve 438 is prolonged by making the value of the anode resistor 443 sufiiciently high. Thus, the negative suppressing impulse delivered to valve 4|! will not be removed therefrom until after the removal of the positive impulse delivered from valve 405. All this prevents the delivery of a negative impulse to the signal line 42 The anodes 424 and 434 respectively of signal gating valves 422 and 432 are also connected to the inner control electrode 448 of a signal input valve 450 by means of a coupling capacitor 45L Signal input valve 458 which is normally nonconducting has it inner control electrode 448 negatively biased by its return to negative bus 9 through a grid resistor 449. The suppressor electrode 452 and the cathode 453 of valve 450 are grounded, and the screen electrode 454 is linked to positive bus 10 and connected to ground through a bypass capacitor 455. The anode 456 of input valve 450 connects to positive bus 90 through an anode resistor 451 and is coupled to a signal line 40| through a delay line 458 by connecting to the input thereof.

The delay line 458 comprises a plurality of series connected inductors 459, an input resistor 462 bridging to ground the input end of said inductors 459, and a plurality of capacitors 460 each connecting the end of an inductor 459 to ground. The output end of delay line 458 connects to signal line 46 When both gating valves 422 and 432 become nonconductive at the same time, a positive-going signal developed upon their anodes 424 and 434 is delivered to the inner control electrode 448 of signal input valve 450. The valve 450 becomes conductive producing a negative-going signal upon its anode 456. This negative signal is delivered to the signal line 48| after a delay of approximately one pulse period at the given repetifiion rate. This delay is imposed by the delay line Thus, if a negative impulse is delivered to either of the impulse receiving terminals 40 402 but not to both, a negative impulse is delivered to the signal line 42|. If negative impulses arrive upon both impulse-receiving terminals 40| and 402 at 17 the same time, a signal is-not delivered to line 42 I, however, anegative impulse is delivered to the signal line it! after a one impulse period delay.

The portion of the impulse responsive circuit shown in Figure 4 thus far described can be considered to be one stage of a tivo stage network. The second stage to be described now is in many respects similar to the first stage. The signal line 52! connects to the inner control electrode 504 of a signal buffing valve 555 and to the control electrode 520 or" a signal gating valve 522. The signal line 46| is joined to the auxiliary control electrode 551 of the bufiing valve 555 and connects to the control electrode 52l of the signal gating valve 532.

The signal buffing valve 555, which is normally conducting, has its anode returned to the positive bus 55 through an anode resistor'5l3 and linked to a signal output terminal 550 by means of a coupling capacitor 5i-4 through a delay network 5! 5.

The output end of the delay network 5I5 also connects to the control electrode 5 l 6 of a normally nonconducting signal inverting valve 5 l I. The control; electrode sue is negatively biased by returning to negative bus 5 through grid resistor 5H3. The inverting valve 5!! has its anode joined to positive bus 90 through an anode, resistor 5l9 and linked to signal output terminal 52! through a coupling capacitor 525.

The normally conducting gating valves 522 and 532 have their anodes returned through an anode resistor 535 to positive bus 95 and linked to the control electrode 535 of a signal inverting valve 538 through a coupling resistor 540. The control electrode 539 of the normally nonconducting inverting valve 538 is negatively biased by returning through a grid resistor 54! to negative bus 30! the anodeof valve 538 is returned to positive bus 9!! through an anode resistor 543 and 1 joined to the input electrode 5115- of the signal inverting valve 5H.

The anodes of signal gating valves 5-2-2 and 532 are further connected to the inner control elsetrode 548 of the signal input valve 550 by means of a coupling capacitor 55L Theinner control electrode 5480f valve 450 is negatively biase'd by returning to negative bus 9 'througha grid resistor see. A positive impulse upon either of the control electrodes 54-5, 448 of signal input valve Q55 is sufficient to render this valveconductive;

The operation of valves 505; 5H, 522', 53-2, and 538 are respectively similarto the operation. of the valves 405, 4-H, 422, 4132-, and 438;previou'sly described. Thus, when a negative impulse arrivesupon the signalline 421, a positive impulse is delivered to the output terminal 550-, while a negativeimpulse is delivered to: the outputterminal 52!. When a negative impulse arrives upon the signal line 461, a positive impulse is likewise delivered to terminal 550, while a negativeimpulse is deliveredto terminat52t. Whennegative impulses. arrive upon the signal lines'42 i' and 46l at the same time,signals are not delivered to the output terminals 550 and 521,.however, ane'gative impulse is delivered tothe innercontrol electrode Mil-of the signal input valve 455;. This results in a negativeimpulse upon line 4-6l after a. delay of approximately one pulse period; Positive impulses cannot be received at'the same time by bothcontrol electrodes 548and 448, of the signal input valve 450; for reason-salready explained in connection with Figure 1.

The impulse response of. the circuit: shown i Figure 4 to sets of irripulsetrains,- is similar to 18 that of the impulse responsive circuits shown in Figures 1 and 4.

The first stage portion of the circuit shown in Figure 4 may be utilized as previously described for the first stages of the impulse responsive circuits shown in Figures 1 and 3. This circuit may be provided with two signal output lines, namely lines 42! and 46!. The output response of the circuit to input impulse signals is similar to that of the first stage portions of the responsive circuits shown in Figures 1 and 3.

While only a few representative embodiments of apparatus for practising the inventions disclosed herein have'been outlined in detail. there will be obvious to those skilled in the art, many modifications and variations accomplishing the foregoing objects and realizing many or all of the advantages, but which yet do not depart essentially from the spirit of the invention.

What is claimed is:

1. In an impulse responsive network, a first circuit comprising first and second input conductors adapted to receive stimuli and first and second output conductors, said first output conduc tor being energized upon the occurrence of stimuli on only one of said input conductors, said second output conductor being energized at a predetermined time after the concurrence of stimuli upon both of said input conductors, and a second circuit comprising first and second input conductors adapted to receive stimuli respectively connecting with the first and second output conductors of said first circuit and first and second output conductors, said first output conductor'being energized upon the occurrence of stimuli on only one of said input conductors, said second output conductor energizing the second-input conductor of said second circuit at a predetermined time after the concurrence of stimuli upon both of the input conductors of said second circuit.

2. In an impulse responsive network, a first circuit comprising first and second input conductors adapted to receive stimuli and first and second output conductors, said first output conductor being energized upon the occurrence of stimuli on only one of said input conductors,. said second output conductor being energized upon the concurrence of stimuli upon both of said input conductors, a delay element having an input lead operatively connecting with the second output conductor of said first circuit and an output lead; and a second circuit comprising first and second input conductors adapted to receive stimuli respectively connecting with the first output conductor of said first circuit and the output lead of said delay element and first and second output conductors, said first output conductor being energized upon the occurrence of stimuli on only one of said input conductors, said second output conductor energizing the input lead of said delay element upon the :concurrence of stimuli on both of the input conductors of said secondv circuit.

3. In an impulse responsive network, a first circuit comprising first and second input conductors adapted toreceive stimuli and first and second output conductors, said first output con ductor" being energized upon the occurrence of stimuli on only one of said input conductors, said second output conductor being energized at a predetermined time after the concurrence of stimuli upon both of said input conductors, a second circuit comprising first and second input conductors adapted to receive stimuli and first andsecond output conductors, saidfirst output conductor being energized upon the occurrence of stimuli on only one of said input conductors, said second output conductor being energized at a predetermined time after the concurrence of stimuli upon both of said input conductors, a first gating connection conditionally passing stimuli on the first output conductor of said first circuit to the first input conductor of said second circuit, stimuli on the second output conductors of said first and second circuits being conditionally passed to the second input conductor of said second circuit, a signal line, and a second gating connection conditionally passing stimuli on the first output line of said second circuit to said signal line.

4. In an impulse responsive network, a first circuit comprising first and second input conductors adapted to receive stimuli and first and second output conductors, said first output conductor being energized upon the occurrence of stimuli on only one of said input conductors, said second output conductor being energized upon the concurrence of stimuli upon both of said input conductors, a second circuit comprising first and second input conductors adapted to receive stimuli and first and second output conductors, said first output conductor being energized upon the occurrence of stimuli on only one of said input conductors, said second output conductor being energized upon the concurrence of stimuli upon both of said input conductors, a delay element having an output lead operatively connecting with the second input conductor of said second circuit and an input lead, a first gating connection conditionally passing stimuli on the first output conductor of said first circuit to the first input conductor of said second circuit, stimuli on the second output conductors of said first and "second circuits being conditionally passed to the input lead of said delay element, a signal line, and a second gating connection conditionally passing stimuli on the first output line of said second circuit to said signal line.

5. In combination, a first signal line, a second signal line, a first signal link, a second signal link, a first bufilng connection between said first signal line and said first signal link, a second buffing connection between said second signal line and said first signal link, a first gating connection adapted to receive stimuli upon said first and second signal lines, said gating connection upon the concurrence of stimuli on said first and second signal lines energizing said second signal link and inhibiting stimulation of said first signal link, a delay element having an input lead operatively connecting with the second signal link and an output lead, a third signal link, a third bufiing connection between said first signal link and said third signal link, a fourth bufiing connection between the output lead of said delay element and said third signal link, a second gating connection adapted to receive stimuli over said first signal link and upon the output lead of said delay element, said gating connection upon the concurrence of stimuli on said first signal link and upon the output lead of said delay element energizing said second signal link and inhibiting stimulation of said third signal link.

6. In combination, a first signal line, a first bufiing valve comprising a first control electrode a second control electrode and an output electrode, a first delay element connecting between said first signal line and the first control electrode of said first buffer valve, a second signal line, a second buffing valve comprising a first control electrode a second control electrode and an output electrode, a second delay element connecting between said second signal line and the first control electrode of said second bufiing valve, a first signal link operatively connecting with the output electrodes of said first and second buffing valves, a second signal link, and a gating valve comprising a first control electrode connecting with said first signal line a second control electrode connecting with said second signal line and an output electrode coupled with the second control electrodes of said first and second bufiing valves and with said second signal link, said gating valve upon the concurrence of stimuli upon said first and second signal lines energizing said second signal link and inhibiting stimulation of said first signal link.

'7. In combination, a first signal line, a second signal line, a first bufiing valve comprising a control electrode operatively connecting with said first signal line and an output electrode, a second buffing valve comprising a control electrode operatively connecting with said second signal line and an output electrode, a first signal link comprising an electrode structure including a control member and an output member, a delay element operatively connected between the output electrodes of said first and second buffing valves and the control member of said first signal link, a second signal link, a gating valve comprising a first control electrode connecting with said first signal line a second control electrode connecting with said second signal line and an output electrode connecting with the output member of said first signal link and with said.

second signal link, said gating valve upon the concurrence of stimuli upon said first and second signal lines energizing said second signal link and inhibiting stimuli upon the output member of said first signal link.

8. In combination, a, first signal line, a second signal line, a first bufiing connection having a pair of input elements respectively connecting with said first and second signal lines and an output element, a first coupling connection comprising an input member connecting with said first signal line and an output member, a second coupling connection comprising an input member connecting with said second signal line and an output member, a first inverting connection comprising an input member connecting with the output members of said first and second coupling connections and an output member connecting with the output element of said first bufling connection, a second buffing connection having a first input element connecting with the output element of said first bufling connection and an output element, a delay link comprising a first unilateral input conductor connecting with the output members of said first and second coupling connections an output conductor connecting with the second input element of said second bufiing connection and a second unilateral input conductor, a third coupling connection comprising an input member connecting with the first input element of said second buffing connection and an output member, a fourth coupling connection comprising an input member connecting with the second input element of said second bufling connection and an output member, the output members of said third and fourth coupling connections connecting with the second unilateral input conductor of said delay link, and a second inverting connection compris- 21 ing an input member connecting with the output members of said third and fourth coupling connections and an output member connecting with the output element of said second buffing connection.

9. In combination, a first signal line, a second signal line, a bufilng connection having a pair of input elements respectively connecting with said first and second signal lines and an output element, a first coupling connection comprising an input member connecting with said first signal line and an output member, a second coupling connection comprising an input member connecting with said second signal line and an output member, an inverting connection comprising an input member connecting with the output members of said first and second coupling connections and an output member connecting with the output element of said bufiing connection, and a transfer delay link having an input lead connected to the output members of said first and second coupling connections and an output lead.

10. In combination, a first signal line, a second signal line, a buffing connection having a pair of input elements respectively connecting with said first and second signal lines and an output element, a first coupling connection comprising an input member connecting with said first signal line and an output member, a second coupling connection comprising an input member connecting with said second signal line and an output member, and an inverting connection comprising an input member connecting with the output members of said first and second coupling connections and an output member connecting with the output element of said buffing connection.

11. In combination, a first signal line, a second signal line, a signal output line, a bufling valve comprising a first control electrode connecting with said first signal line a second control electrode connecting with said second signal line and an output electrode, a delay element connecting between the output electrode of said buffing valve and said signal output line, a first coupling valve comprising a control electrode connecting with said first signal line and an output electrode, a second coupling valve comprising a control electrode connecting with said second signal line and an output electrode, and a signal inverting valve comprising a control electrode connecting with the output electrodes of said first and second coupling valves and an output electrode coupled with said signal output line.

JOHN PRESPER ECKERT, JR. JOHN W. MAUCHLY.

REFERENCES CITED UNITED STATES PATENTS Name Date Smith et al. Mar. 15, 1949 Number 

